CVE-2021-34749
5.8 · MEDIUMOverview
CVE-2021-34749 is a medium-severity vulnerability affecting cisco ironport_web_security_appliance. It was published on August 18, 2021 and has a CVSS 3.1 base score of 5.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
A vulnerability in Server Name Identification (SNI) request filtering of Cisco Web Security Appliance (WSA), Cisco Firepower Threat Defense (FTD), and the Snort detection engine could allow an unauthenticated, remote attacker to bypass filtering technology on an affected device and exfiltrate data from a compromised host. This vulnerability is due to inadequate filtering of the SSL handshake. An attacker could exploit this vulnerability by using data from the SSL client hello packet to communicate with an external server. A successful exploit could allow the attacker to execute a command-and-control attack on a compromised host and perform additional data exfiltration attacks.
Remediation
Check the references section for vendor advisories and patches from cisco. Update ironport_web_security_appliance to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
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References
Frequently Asked Questions
What is CVE-2021-34749?
CVE-2021-34749 is a medium-severity vulnerability affecting cisco ironport_web_security_appliance. It was published on August 18, 2021 and has a CVSS 3.1 base score of 5.8 (MEDIUM).
How severe is CVE-2021-34749?
This vulnerability has a CVSS 3.1 base score of 5.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-34749?
Check the references section for vendor advisories and patches from cisco. Update ironport_web_security_appliance to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-34749?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-34749 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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